3D modeling involves the use of special software to create images in three dimensions. Some of the common uses of 3D modeling are in creating the arcade and video games, animation films, motion pictures, medicine and the fashion industry. One of the most popular uses of 3D modeling is in real estate. Architects and designers use 3D modeling to get a view of the final structure they propose to build, while firms are using 3D modeling to explain their strong points to clients. Irrespective of the use, 3D modeling can be of the following types:
This type of 3D modeling mostly uses spheres, cubes and other variations of these two shapes to put together the desired shapes. It is called primitive because it is a very rudimentary form of 3D modeling. This kind of modeling generally utilizes basic Boolean processors to get the right shapes and outlines.
This type of modeling is used for situations where the shape of the final output resembles some or the other polygon. The designers start by creating a wire mesh in the desired shape of the polygon. Therefore, they need to have a good working knowledge of polygonal mesh theory. The most common use of this type of 3D modeling is in scanline rendering.
Rational B-Spline Modeling
This is the most common type of 3D modeling. This also bases its technology on polygons and starts by creating the polygon shapes. These shapes are then twisted and curved to give the required shape. One of the reasons for the popularity of Rational B-Spline Modeling is that is easy to handle and to master.
In reality, though, there are scores of techniques in use, many of which often combine to form more well-known types. Let us look at the most common of them:
Photogrammetry is a process by which special photography software like Photo Scan is used to create three-dimensional figures using photographs taken from different angles.
- Some designers spread smaller particles over the surface of the object that is to be distributed, creating a wonderful three-dimensional model.
- There are specific modeling tools like BLAM which help to create a lifelike workflow based on sequentially calibrating a series of photographs of the same subject.
- Most of the software packages or the DIY tools use mathematical formula at the backend. This is done by describing every position of a moving object regarding coordinates on a grid — the cumulation of these x and y coordinates of a particle crate a line, then a surface, and finally a solid.
- A very complicated yet popular way of generating solid shapes is by the use of fractals. Most designers nowadays use apps to create different fractals, but for those who are interested in first principles, a fractal is a unique figure which has the same statistical flavour as any smaller portion of it.
- Many designers favour a unique three-dimensional shape called a voxel. It is a cell occupying certain volume in a three-dimensional space. Different architectural elements can be represented in a 3D model using these units.
- Some architects and interior designers prefer to use pre-built kits for their three-dimensional models. The standard shapes can then be put together as per the requirement without needing to generate new shapes.
- Just like rendering can provide two-dimensional results, the use of vector graphics can help to convert standard vector graphics (in two dimensions) into three-dimensional splines. These splines can then be used to depict a flowing surface which morphs into a solid shape on being wrapped around.
- After a wire mesh has been created, a portion of it is sometimes extracted to use as the starting point for a new surface.
- Orthographic projection is a popular method favoured by many designers. This method uses the faces and edges of planar surfaces to generate two-dimensional drawings, which can later be used to generate shapes and forms.
- Just like we mentioned regarding primitive modeling above, Boolean operators are some of the most common ways of generating three-dimensional surfaces and shapes. Designers add or subtract two different objects to create a new object.
- The last category we will discuss here as part of this smaller list is Dynamic Topology. It is similar to the process of sculpting using masks or stencils. The additional feature in dynamic topology is that it makes use of additional polygons to complete the shape.
There is one more category of 3D modeling that is very elegant and therefore very popular, which is why we wish to discuss it separately here. This is called Non-Uniform Rational Basis Spline, or NURBS for short. It is an elegant mathematical model which can be used in a variety of scenarios to create realistic curves and surfaces. The beauty of NURBS is that it can operate independently as an efficient program, but it also welcomes human intervention when required to make the final product much better.
As we saw above, there are some techniques and types of 3D Modeling. Each of these can be used according to the skillsets and the requirement of the designer to produce useful outcomes. Each technique and type have their own useful attributes and hence, it is important to take into consideration, which of them is used at what point.